Sudden cardiac death (SCD) in young competitive athletes is rare but has led to calls for screening. The rationale seems simple: if only we had known we might have been able to prevent the catastrophe. Yet even if this were true, it would require screening of many hundreds of thousands of cases to identify high-risk individuals and respond appropriately. Hypertrophic cardiomyopathy (HCM) is the single most common cause of SCD in young people, contributing to around a quarter of cases, and was looked at by the UK's National Screening Committee (NSC) in 2010, with more recent attention given to other causes of SCD.1 A consultation document is now in preparation, but meanwhile I present some of the issues that require consideration when proposing a national screening programme.

First it is prudent to refer to some of the classical screening appraisal criteria set out in the 1950s by Wilson and Jungner.2 (1) How common is the problem? (2) What is the natural history of the disorder and the appropriate timing of intervention? (3) Is there an accurate test? (4) Once diagnosed, is there effective treatment? (5) Are services in place to deliver the required number of diagnostic tests, interpret the results and manage those who are test positive? (6) Is the screening programme affordable and acceptable? (7) Has the effectiveness of the proposed screening programme been adequately tested, ideally in a randomised trial?

Applying these criteria to SCD in young competitive athletes reveals the profound difficulty of implementing an effective screening programme. To begin …